Posterior Vagal Trunk

truncus vagalis posterior

The right vagus nerve comes to lie on the posterior surface of the oesophagus as it descends through the thorax, forming the posterior vagal trunk at the oesophageal hiatus. It passes through the diaphragm with the oesophagus and distributes primarily to the posterior stomach, the celiac and superior mesenteric plexuses (the large celiac branch), and indirectly to the small intestine, colon to the splenic flexure, pancreas, and small bowel via the celiac plexus relay.

Region: Abdomen

Clinical Relevance

Clinical Notes

The posterior vagal trunk is identified on the posterior oesophageal wall during hiatal hernia repair and vagotomy. Its large celiac branch to the celiac plexus carries the parasympathetic supply to most of the abdominal viscera. Truncal vagotomy divides both anterior and posterior trunks at the oesophageal hiatus to reduce acid secretion, but requires a drainage procedure (pyloroplasty or gastrojejunostomy) because division of the posterior trunk's antral branches causes pyloric spasm and gastric outlet obstruction.

Pathology

Common Injuries & Conditions

Truncal Vagotomy and Drainage

Division of both vagal trunks at the oesophageal hiatus eliminates vagal-mediated gastric acid secretion and antral peristalsis, requiring a simultaneous pyloroplasty or gastrojejunostomy to prevent gastric retention from pyloric spasm, a historical procedure now largely replaced by proton pump inhibitor therapy.